A Large Dynamic Range Charge Amplifier ADC for the Fermilab Collider Detector Facillity

A multi-channel charge amplifier ADC system for use with electromagnetic and hadronic calorimetry has been built with Xl and X16 amplifier channels which extend the range of the single 16 bit ADC to the equivalent of a 20 bit system having 0.7 fC least significant resolution. Two on-board calibration schemes, a fast analog trigger output, and redundant readout are also included. The point-wise error in linearity (expressed as the maximum error as a percentage of the full charge scale) is less than 0.02% for the Xl channels, and less than 0.002% for the X16 channels. Other features include a Before/After signal differencing scheme which provides low frequency noise rejection and compensation for baseline drifting, and temperature stability on the order of 30 ppm/C.